Both are storage arrays (SANS). Basically redudant controllers (storage processors is what NetApp call them) attached to shelves of physical disk. Generally the disks are either fibre channel (high performance and cost) or SATA/FATA (low cost for archiving/storage) but some SAS disks and solid state are creeping in. These allow servers to use shared storage (for clustering, VMWare etc) or higher performing storage (more disk spindles) and present LUNs (blocks of disks carved out of a pool) as local hard disk to servers.

The HP EVA (Enterprise Virtual Arrays) is a mid level array (the high leve HP SANs are the XP - which are actually OEM Hitachi) that comes in three models (4000 series, 6000 series and 8000 series) with the main difference between each model being processor and memory/cache on the controllers and the number of shelves of disk they support. HP EVAs support one method of connectivity which is fibre channel. It is possible to use iSCSI but this requires an addtional model to be plugged into your FC switch.

EVAs use what they like to call v-raid (sits on top of RAID 5 arrays with a sweet spot of eight disks with the data striped across multiple arrays). They also support RAID 1+0 from memory. HP EVAs are capable of taken snapshots of data if required
From a recent comparison I did, before purchase, the HP EVAs come in much cheaper than NetApp or EMC.

NetApp have a wider range than HP EVAs - but they don't have multiple classes (i.e. HP have EVA and XP, EMC have Clarrion and Symmetrix) - which is good if you want a high end model for production but are happy with a low end model for DR. Again the model differences are cpu and memory/cache and how many shelves of disk they can manage.

NetApp support both iSCSI and FC protocols but also support file protocols such as CIFS and NFS - i.e. can act as a NAS as well for your file server data, unix boxes and VMWare if required. They also support deduplication, vmware, sql, exchange and oracle snapshots via a GUI - of course you have to pay for each extra you get. NetApp use what they like to call RAID DP (double parity) which is their version of RAID 6 - with a sweet spot of 16 disks, two dedicated for parity, per array. On top of this (where HP uses V-raid) they put an aggregate - again all your data is striped across multiple arrays for better space utilisation and capacity. They also support RAID 4

Both are quite good and would meet most needs (snapshots, redundancy, performance, storage virtualisation etc) but NetApp comes with many more options and better performance (but a larger price tag). I recently did a large comparison and test on EMC Clarrion CX3-40, HP EVA 8800 and NetApp FAS 3140 and based on a weighting document selected NetApp - but it is hourses for courses and I would get the one that best fit your needs and budget.

Featured Post

Work with freelancers specializing in everything from database administration to programming, who have proven themselves as experts in their field. Hire the best, collaborate easily, pay securely, and get projects done right.